COX3_PYLLI
ID COX3_PYLLI Reviewed; 272 AA.
AC Q37600;
DT 15-JUL-1998, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1996, sequence version 1.
DT 25-MAY-2022, entry version 90.
DE RecName: Full=Cytochrome c oxidase subunit 3;
DE EC=7.1.1.9;
DE AltName: Full=Cytochrome c oxidase polypeptide III;
GN Name=COX3;
OS Pylaiella littoralis (Seaweed) (Conferva littoralis).
OG Mitochondrion.
OC Eukaryota; Sar; Stramenopiles; Ochrophyta; PX clade; Phaeophyceae;
OC Ectocarpales; Acinetosporaceae; Pylaiella.
OX NCBI_TaxID=2885;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA Fontaine J.-M., Rousvoal S., Delaroque N., Loiseaux-De Goer S.;
RT "Characterisation of the cox3, nad7 and atp6 genes from the mitochondrial
RT genome of the brown alga Pylaiella littoralis.";
RL Plant Physiol. Biochem. 33:605-609(1995).
CC -!- FUNCTION: Component of the cytochrome c oxidase, the last enzyme in the
CC mitochondrial electron transport chain which drives oxidative
CC phosphorylation. The respiratory chain contains 3 multisubunit
CC complexes succinate dehydrogenase (complex II, CII), ubiquinol-
CC cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III,
CC CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to
CC transfer electrons derived from NADH and succinate to molecular oxygen,
CC creating an electrochemical gradient over the inner membrane that
CC drives transmembrane transport and the ATP synthase. Cytochrome c
CC oxidase is the component of the respiratory chain that catalyzes the
CC reduction of oxygen to water. Electrons originating from reduced
CC cytochrome c in the intermembrane space (IMS) are transferred via the
CC dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1
CC to the active site in subunit 1, a binuclear center (BNC) formed by
CC heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2
CC water molecules using 4 electrons from cytochrome c in the IMS and 4
CC protons from the mitochondrial matrix. {ECO:0000250|UniProtKB:P00420}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=4 Fe(II)-[cytochrome c] + 8 H(+)(in) + O2 = 4 Fe(III)-
CC [cytochrome c] + 4 H(+)(out) + 2 H2O; Xref=Rhea:RHEA:11436,
CC Rhea:RHEA-COMP:10350, Rhea:RHEA-COMP:14399, ChEBI:CHEBI:15377,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033,
CC ChEBI:CHEBI:29034; EC=7.1.1.9;
CC Evidence={ECO:0000250|UniProtKB:P00420};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437;
CC Evidence={ECO:0000250|UniProtKB:P00420};
CC -!- SUBUNIT: Component of the cytochrome c oxidase (complex IV, CIV), a
CC multisubunit enzyme composed of a catalytic core of 3 subunits and
CC several supernumerary subunits. The complex exists as a monomer or a
CC dimer and forms supercomplexes (SCs) in the inner mitochondrial
CC membrane with ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1
CC complex, complex III, CIII). {ECO:0000250|UniProtKB:P00420}.
CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC {ECO:0000250|UniProtKB:P00420}; Multi-pass membrane protein
CC {ECO:0000250|UniProtKB:P00420}.
CC -!- SIMILARITY: Belongs to the cytochrome c oxidase subunit 3 family.
CC {ECO:0000305}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR EMBL; Z37967; CAA86022.1; -; Genomic_DNA.
DR PIR; S57460; S57460.
DR RefSeq; NP_150402.1; NC_003055.1.
DR AlphaFoldDB; Q37600; -.
DR SMR; Q37600; -.
DR GeneID; 803717; -.
DR GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell.
DR GO; GO:0004129; F:cytochrome-c oxidase activity; IEA:UniProtKB-EC.
DR GO; GO:0019646; P:aerobic electron transport chain; IEA:InterPro.
DR CDD; cd01665; Cyt_c_Oxidase_III; 1.
DR Gene3D; 1.20.120.80; -; 1.
DR InterPro; IPR024791; Cyt_c/ubiquinol_Oxase_su3.
DR InterPro; IPR033945; Cyt_c_oxase_su3_dom.
DR InterPro; IPR000298; Cyt_c_oxidase-like_su3.
DR InterPro; IPR035973; Cyt_c_oxidase_su3-like_sf.
DR InterPro; IPR013833; Cyt_c_oxidase_su3_a-hlx.
DR PANTHER; PTHR11403; PTHR11403; 1.
DR Pfam; PF00510; COX3; 1.
DR SUPFAM; SSF81452; SSF81452; 1.
DR PROSITE; PS50253; COX3; 1.
PE 3: Inferred from homology;
KW Membrane; Mitochondrion; Mitochondrion inner membrane; Translocase;
KW Transmembrane; Transmembrane helix.
FT CHAIN 1..272
FT /note="Cytochrome c oxidase subunit 3"
FT /id="PRO_0000183840"
FT TRANSMEM 20..40
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 45..65
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 89..109
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 128..148
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 166..186
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 204..224
FT /note="Helical"
FT /evidence="ECO:0000255"
FT TRANSMEM 248..268
FT /note="Helical"
FT /evidence="ECO:0000255"
SQ SEQUENCE 272 AA; 30628 MW; B9EFF7803A08E8DD CRC64;
MKSTAKMIQR HPFHLVDPSP WPLVAALGGL SLTFGGVLFM HNYEGGGELL CLGFFTILYV
MFTWWRDVIR EALFEGQHTL AVQQGLRMGM ILFIVSEIMF FFAFFWAFFT SSISPVFNIG
GVWPPTDVVA ISPWGLPFLN TILLLSSGAS VTWAHHAIVG GLKKEAMQGL SVTLAFAIAF
TAMQGFEYSG APFGMSDGVY GSVFYMATGF HGFHVIIGTI FLFICTIRLY LSHFSCQHHF
GFEAAAWYWH FVDVVWLFLF LTIYWWGFNI TV
